Without limiting the scope of the invention, its background is described in connection with carcinoma of the genito-urinary tract, as an example. Bladder carcinoma is one of the most common forms of cancer of the genito-urinary tract accounting for 51,000 new cases and 11,000 deaths each year. Bladder cancer is the fourth most common cancer in men and the eighth most common in women, with transitional cell carcinoma (TCC) of the bladder is the most common urothelial malignancy of the urinary tract accounting for about 90% of all bladder tumors. Seventy percent of patients with an initial diagnosis of transitional cell carcinoma have superficial tumors, which can be treated by transurethral resection alone.
The difficulty in detecting and treating bladder cancer makes it a serious concern. Generally, bladder carcinomas are heterogeneous in their ability to progress, e.g., transitional cell carcinomas. TCCs are classified by Grade and depth of invasion (e.g., stage). For example, some TCCs are considered low-grade (e.g., G1 tumors) mostly confined to the mucosa (stage Ta) and behave in a benign fashion, whereas others are intermediately-grade (e.g., G2 tumors) which are moderately aggressive and range from being non-invasive (stage Ta) to invasive (stages T1-T4) with highly aggressive lymphatic and vascular invasion and local and distant metastases, e.g., G3 tumors and carcinoma in situ (CIS).
The high-grade tumors (e.g., bladder tumors) often metastasize rapidly and the invasive disease may already exist at the time of clinical presentation (e.g., hematuria, irritative voiding symptoms etc.). For example, half of the patients develop distant metastasis within two years of diagnosis despite surgery and 60% of them die within 5 years. Additionally, tumor recurrence is a characteristic of bladder carcinoma. As a result of the malignant nature of TCCs, it is critical for detection prior to muscle invasion.
Detecting tumor recurrence in patients with transitional cell carcinoma of the bladder requires close surveillance. Presently, cystoscopy, bladder washings and biopsies are common method to detect and monitor bladder cancer. Many of these procedures are invasive and lack the necessary specificity to adequately diagnose bladder cancer. Urine cytology is a common non-invasive procedure for the diagnosis of bladder cancer; however, it can miss up to 50% of tumors. For example, urine cytology has a low specificity due to its subjective nature. Other detection method may have a high sensitivity, but have a low specificity and detect (e.g., false positive) benign genito-urinary conditions (e.g., kidney stones, benign prostatic hyperplasia etc). Another form of diagnosis is cystoscopy, which allows visualization and direct biopsies of suspicious bladder lesions in the mucosa; however, cystoscopy is invasive and expensive procedure, which cannot be used as a general screening tool for the detection of bladder cancer. For example, other detection methods include tests that detect bladder tumor antigens, e.g. NMP-22. Generally, these tests detect altered expression of proteins or enzyme activity that can be associated with malignancy, or genetic alterations in urinary cells and bladder washings. These procedures often use fluorescence in situ hybridization (FISH) and microsatellite analysis, which is time consuming and costly, as large numbers of cells must be analyzed to obtain an accurate analysis.
Apoptosis is indispensable for normal development, homeostasis of multicellular organisms and defense in that it is the process responsible for cellular destruction and elimination of mutated (e.g., tumors), damaged, or virally infected cells through induction of apoptosis. In many physiologic processes the primary mediator of apoptosis (e.g., tumor cell death) is the cytotoxic T-cells and natural killer cells which also maintenance of immune privileged sites such as the eye, testis, brain, and maternal-fetal interface. A transmembrane cell-surface protein termed Fas regulates apoptotic or programmed cell death through the intercellular interactions of Fas with ligands or effectors. Generally, the interaction between Fas and Fas ligand (FasL) induces apoptosis in cells through activation of the intracellular Fas-associated domain. Natural killer cells and cytotoxic T-cells express the Fas receptor, which engages the Fas-FasL interaction and induce apoptosis of cancer cells through proteolysis and degradation of chromosomal DNA. The Fas signaling pathway consists of a 48 kDa cell surface glycoprotein protein termed Fas protein (also designated CD95L, APO-1). Fas and FasL belong to the TNF (Tumor Necrosis Factor) family, which include CD 40, nerve growth factor receptors and tumor necrosis factor receptors. Specifically, Fas is a member of the of the transmembrane receptor family, while FasL is member of the membrane-associated cytokine family.
Fas plays a role in several pathophysiological conditions including cancer. Fas mRNA and Fas protein expression is altered in certain carcinomas when compared with the corresponding normal tissue expression, which in turn alters cytotoxic T-cells and natural killer cells via the expression of the Fas receptor that engages the Fas-FasL interaction to induce apoptosis of cancer cells. Dysregulation of Fas-mediated apoptosis is thought to play a role in the development and progression of various tumors, e.g., alternative splicing of Fas mRNA can generate soluble forms of Fas that have a deletion or disruption of the membrane-spanning domain. Additionally, FAS mRNA and protein expression increased substantially from normal to prostatic intraepithelial neoplasia, to low grade, to high grade, and to androgen-independent bone metastases. Prior to the present invention, the correlation between components of the FAS system in the urine affect the proliferation of human endothelial cells.
The foregoing problems have been recognized for many years and while numerous solutions have been proposed, none of them adequately address all of the problems in a single device, e.g., high specificity, invasiveness, reproducibility, and reliability.